Method for repairing flexible materials

ABSTRACT

Damaged, flexible vinyl materials, such as automobile seats and tops, are repaired by a welding compound which is grained and colored to match the base material. The damaged section of the base material is prepared by removing frayed edges and the like to obtain a clean, sharp periphery. The base material is cleaned by a solvent to ensure adhesion or fusion of the welding compound with it. The welding compound is a vinyl compound which has a relatively high tensile strength and relatively low fusion point. This compound is applied in layers to the cutout area of the base material, with each layer being cured after it is applied. The final layer is smoothened to present a continuous, uninterrupted surface from the base material across the weld compound material. A graining tool, which is both hard and flexible, is obtained from an impression of the base material or material having the same grain structure. The graining tool is applied to the upper surface of the cured welding compound after it and the surrounding base material have been heated sufficiently to receive the grain impression.

United States Patent [72] Inventor Harvey J. cabal Bit" 15 17 SunriseLn., Fullerton, Calif. 92633 [21] Appl. No. 808,762 [22] Filed Mar. 20,1969 [45] Patented Nov. 16, 1971 [73] Assignees Harvey J. Golumbic;

Robert M. Bregofl; Alfred A. Calabro, part interest to each [54] METHODFOR REPAIRING FLEXIBLE MATERIALS 7 Claims, 3 Drawing Figs.

[52] US. I 156/98 [51] Int. Cl B32b 35/00 [50] Field of Search. 156/98,94, 222

[56] References Cited UNITED STATES PATENTS 2,855,338 10/1958 Molkey156/94 3,271,217 9/1966 Mapson l56/98 primary fiainirier -Benjamin A.Borchelt Assistant Examiner-Daniel Bent Attorney-Christie, Parker & HaleABSTRACT: Damaged, flexible vinyl materials, such as automobile seatsand tops, are repaired by a welding compound which is grained andcolored to match the base material. The damaged section of the basematerial is prepared by removing frayed edges and the like to obtain aclean, sharp periphery. The base material is cleaned by a solvent toensure adhesion or fusion of the welding compound with it. The weldingcompound is a vinyl compound which has a relatively high tensilestrength and relatively low fusion point. This compound is applied inlayers to the cutout area of the base material, with each layer beingcured after it is applied. The final layer is smoothened to present acontinuous, uninterrupted surface from the base material across the weldcompound material. A graining tool, which is both hard and flexible, isobtained from an impression of the base material or material having thesame grain structure. The graining tool is applied to the upper surfaceof the cured welding compound after it and the surrounding base materialhave been heated sufficiently to receive the grain impression.

METHOD FOR REPAIRING FLEXIBLE MATERIALS BACKGROUND OF THE INVENTION Thepresent invention relates to a process for repairing flexible articlesand, more in particular, to a process for repairing vinyl base materialsuch as automotive upholstery and vinyl tops.

Vinyl materials have become extremely popular for use in automobiles,home furnishings and the like. The surface of vinyl materials can betextured to simulate almost any pattern desired. An example of this issimulated leather upholstery of vinyl.

As in most materials, vinyl materials can become damaged. Damage to thematerial by cigarette burns, knife cuts, tears, splits and the like isnot uncommon.

Heretofore, there has been no effective way of repairing damage to vinylbase materials because the repair did not mirror the qualities of thebase material. Thus, a repair might be hard, but vinyl material isflexible; orthe repair might be smooth, while the vinyl base material isgrained. Oftentimes the repair, upon aging or curing, lost its adhesionto the base material, whereupon the repair became useless.

For the lack of an effective means of repairing damaged vinyl articlesesthetically, their owners were confronted with expensive reupholsteringor living with damaged articles.

Therefore, there is a need for an effective and cheap method forrepairing vinyl articles which produces a repair of substantially thesame quality as the undamaged base material.

SUMMARY OF THE INVENTION The present invention envisions the use of aflexible, high strength and relatively low fusion point welding compoundof a vinyl base material applied in layers in a prepared area of adamaged vinyl article which, after curing, is grained and colored ifdesired.

In more specific fonn, the method of the present invention includesapplying layers of a welding compound in a prepared hole in the vinylbase material to be repaired. An initial layer is applied over backingmaterial, for example, the roof of an automobile in the case of a repairto a vinyl top, or sponge rubber in he case of a repair to an automobileseat. This layer is cured by heat and allowed to cool. An intermediatelayer, or layers, is applied in identical fashion to the first layer,and finally, a final layer is applied. Before curing the final layer, itis smoothened or leveled to present a repair which is continuous withthe surface of the vinyl base material being repaired. After leveling,the last layer is cured by heat.

When a grain texture is to be applied to the welding compound, agraining tool having a die face with the required grain pattern isapplied to the upper layer of the welding compound after it is heatedand after it is cured. The upper layer is heated to soften the surfaceof the layer and adjacent vinyl material surrounding the layer forreception of the impression of the die. The die is applied to thisheated area under pressure. The die is sufiiciently large in area tofeather the surface of the base material proximate the repair. Theresultant surface is cooled before removal of the graining tool, as bycooling the graining tool with a wet cloth or sponge.

If desired, the repaired area of the vinyl base material may becolor-sprayed with a vinyl color spray.

The process of the present invention provides an expedient and cheap wayof repairing flexible vinyl materials which have been damaged as byripping, tearing, burns or the like. The process produces a repair whichis essentially identical in appearance to the vinyl base material beingrepaired.

These and other features, aspects and advantages of the presentinvention will become more apparent from the following description,appended claims and drawings.

BRIEF DESCRIPTION OF THE FIGURES FIG. I is a depiction of an initiallayer of weld compound applied in a repaired hole of a flexible vinylmaterial such as a vinyl top of an automobile roof;

FIG. 2 is a view similar to FIG. 1 showing the repair after intermediatelayers of welding compound have been applied; and

FIG. 3 is a view showing the finishing of a repair.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The process of the presentinvention contemplates the preparation of a damaged area in a vinyl basematerial by removing loose, damaged and frayed vinyl base material. Thiscan be done with a sharp instrument such as a knife or razor blade. Theobject is to get a clean and sharp edge bounded on one side by the areato be repaired and on the other with undamaged vinyl. In the event thatthe repair is to a razor-type cut, the cut or slit is opened by cuttinga little base material away to develop a wider slit, for example, abouta one-sixteenth of an inch. This provides room for the vinyl weldingcompound, hereinafter described, and ensures a strong fusion bondbetween the welding compound and the base material being repaired.

Further preparation of the joint may be required where the vinylmaterial is glued to a substrate such as a car roof. Glue adverselyaffects the curing of the vinyl-welding material and therefore must notbe in the area where such material is applied. The effect of the glue onthe vinyl-welding compound is that the compound will crack. Therefore,any regluing which must be done to the vinyl base material should bedone without allowing glue to get onto the substrate over which thevinyl-welding material is to be applied and to present clean edges forthe vinylwelding material to fuse with.

In order to obtain satisfactory fusion between the vinylwelding compoundand the base material being repaired, it is necessary that the vinylbase material defining the repair hole or slit be thoroughly cleaned.This may be done with any good quality solvent such as toluol which willremove grease and the like to present a clean vinyl surface withoutleaving a residue. In addition to grease removal, it is preferred that amild vinyl solvent be used to clean a small film of vinyl off the areaof the base material bounding the repair hole to be sure that allforeign matter is removed. The removal of foreign matter from thesurface of the vinyl base material bounding the hole is necessary ifedge lifting is to be avoided.

After the area of the surface of the vinyl material to be repaired hasbeen thoroughly cleaned, it must dry. Drying may be done by wiping thesolvent cleaners away and by the application of heat as from acommercially available heat gun. X

The vinyl-welding compound used in repairing a damaged vinyl article isa vinyl compound having a high tensile strength relative to the vinylbase material but with a fusion point compatible with the base material.The requirement of a low fusion point is necessary to prevent damage tothe base material during the curing of the welding compound. Thefollowing table shows satisfactory ingredients for a welding compound.The amounts shown are for a -gallon batch.

TABLE 1 Parts by Weight Diamond PVC 740| 360 lbs. 0.445 Diamond PVC 7]lbs. 0.l50 Diisodecyl Phalate (DIDP) 120 lbs. 0.395 Ferro l777 3,600 g.0.0l0

satisfactory in accommodating both the requisites of tensile strengthand fusion temperature. The diisodecyl phalate is used to increase theflexibility of the welding compound. If too much of this plasticizer isused, the welding compound loses desirable tensile strength. The ferro1777 is a stabilizer. It is a calcium-zinc organic inhibitor. Thecomposition set forth above is a thermoplastic and thermosettingmaterial which must be cured. It has been found that if this compositionis too thick, effective curing is impossible without damaging the vinylbase material. This is so because the amount of heat required to curethe welding compound, when the latter is thick, damages the vinyl basematerial surrounding the welding compound. Stated alternatively, withthe low heat flux required to prevent damage to the vinyl base material,only the surface of a thick layer of weld compound would be cured.

As a consequence, the process of the present invention contemplates thatthe weld compound be layered into the hole in the vinyl base materialand cured after each layer has been applied. Generally speaking, withmost vinyl base material thicknesses, four layers are satisfactory. Thefirst layer must, of course, be backed in order to prevent the compoundfrom sagging through the hole. Normally the backing is provided by seatcushion material or, in the case of vinyl tops, the steel automobileroof. If it is not, then some fonn of backing must be used. Thus, whenthe sponge rubber used in many automobile upholstery applications issplit in the area to be fixed, the sponge rubber split is filled with,for example, cotton.

Another consideration should be observed if grain flattening of thevinyl base material is to be avoided in situations where the substrateabsorbs considerable amounts of the heat applied during curing. Thissituation occurs, for example, in vinyl top repairs where the steelsubstrate absorbs and retains curing heat applied with a heat gun duringsectioning. This applied heat causes the grain of the base material toflatten. To prevent this, an insulating layer of, say cardboard, shouldbe placed between the metal and welding compound.

Each layer of welding material may be applied to the cutout hole asshown schematically in the Figures. The Figures illustrate a substrateor backing l, for example a car roof, a prepared hole 2, and a vinylbase material 3 overlying the substrate and bounding hole 2. An initiallayer 4 is laid over substrate l with, for example, a pallet knife. Thisinitial layer should be worked around the lower edges of the vinyl basematerial surrounding the repaired hole. A fillet 5 is developed betweenthe wall of hole 2 and the balance of the first layer. Care should betaken to remove all excess welding compound material from the upper ortop surface of the vinyl base material before the cure of the initiallayer to prevent roughness on the vinyl base material surrounding therepair. The initial layer is cured as by a heat gun. This layer must becured properly if the resulting weld is to be effective. With thewelding compound specifically discussed above, the cure is effected whenthe weld material becomes clear. This initial layer is fused with thevinyl base material and, therefore, the demarcation shown is notactually present.

After curing, the layer is allowed to cool for the application of theintermediate layers. This may be done by cold water on a wet cloth. Theintermediate layers are applied exactly as the initial layer. Thus thelayers are worked around the edges of the vinyl material defining thehole and are applied thinly in order to have an effective cure. Theresulting repair at this stage is shown in FIG. 2 with the layered andcured welding compound indicated by reference numeral 6.

The final layer is applied just as the initial and intermediate layersare, but is smoothened or leveled flush with the upper surface of thevinyl base material before curing. After it is leveled, as by a palletknife 7, the upper surface is cured, again by the application of heat.The leveled or smoothened repair is indicated by reference numeral 8.Again, it should be emphasized, the repair after curing is fused withthe vinyl base material and therefore the illustrated distinctiveboundary between the two is not in fact present.

listed below in table II.

TABLE II Reichold polyester resin 32-345 450 lbs. Reichold polyesterresin 3 l-l 50 lbs. Calcium carbonate 400 lbs. Talc lbs.

The polyester resin 32-345 has a very good curing rate and is dry to thetouch after it cures, due to the presence of metallic drying agents. Itis resilient but not flexible, that is, it is stiff. The polyester resin3 l-85l is added to enhance flexibility and therefore reduces thestiffness which would result from the ex' clusive use of the polyesterresin 32-345. These polyesters do not adhere to the vinyl material ofthe repair and base material. Both resins are a semisaturated polymerwhere some of the saturated adipic acids have been replaced with somephthalic anhydrides and some of the propylene glycols have been replacedby the more flexible diethylene glycol. Both resins also have a styrenemonomer which forms a polyester monomer with an acid value of frombetween 20 to 25. Resin 31-85] has more diethylene glycol than resin32-345 to add flexibility.

The calcium carbonate is an extender to reduce the cost of the compoundused in fabricating the grain-on tools. The talc has absorptionqualities that are used for the purpose of adjusting viscosity.

A mold release of, say, silicone is placed over the vinyl base material.The grain-on compound just described is poured on a flat, nonporoussurface and mixed with an activator. The activated grain-on compound isthen removed from the surface and applied over the area of the vinylbase material which has been coated with the silicone mold release. Theactivated grain-on compound is then leveled as by a spatula or stick.

Preferably, a backing of a second piece of vinyl having the grain orsurface texture of the piece being repaired is placed on the grain-oncompound before it sets up. The canvas or fabric side of this backingvinyl piece contacts the grain-on compound in order to show the graintexture. Pressure is applied to the grain-on compound and backing stripwhile they are still on the vinyl base material, as by a board or smallweight. After a period of time, the grain-on compound will set andharden. It may then be peeled off the vinyl base material. The resultinggrain-on tool has a die face with the impression of the grain or surfacetexture of the vinyl base material.

The grain-on tool may be registered or indexed with a repetitive patternof the vinyl base material. This is done by aligning the backing vinylpiece with an identical pattern on the base material before the grain-oncompound has set. The backing vinyl piece can then be indexed with thearea of the vinyl base material surrounding the repair.

A grain is applied by the graining tool by softening the surface of theupper layer of weld compound and the adjacent surface of the vinyl basematerial and then applying the grainon tool over the upper surface andadjacent surface of the vinyl base material under pressure. After asmall period of time, for example, 5 seconds, and after cooling thegrain-on tool as by a wet cloth or sponge, the tool is removed. Colormay be applied to the repaired area through a vinyl color spray.

What is claimed is:

l. A process for repairing a damaged area in a vinyl base materialcomprising:

a. preparing an area to be repaired by removing damaged vinyl basematerial to obtain a sharp edge in the vinyl base material which definesan open hole;

cleaning the surface of the base material adjacent the hole;

c. drying the cleaned area;

applying successive thin layers of a liquid thermoplastic andthermosetting vinyl-welding compound having a fusion temperaturecompatible with that of the vinyl base material and a high tensilestrength relative to the vinyl base material into the hole;

working each layer around the edge of the hole to obtain intimatecontact between the vinyl base material and the layers; X

f. curing each layer by the application of heat after each layer hasbeen worked;

g. cooling each cured layer before applying a successive layer toprevent the immediate curing of the successive layer; and

h. smoothening the last layer before it is cured to obtain a continuoussurface between the vinyl base material and such last layer. 7

2. The process claimed in claim 1 including the additional step ofgraining the surface of the cured last layer by:

a. heating the surface of the cured last layer to soften it;

b. applying a graining tool having the grain pattern of the vinyl basematerial in a die face thereof to the softened surface with the die faceon such softened surface;

c. maintaining the graining tool on the softened surface under a slightpressure to obtain a grain therein; and

d. cooling the graining tool while maintaining the slight pressure toallow the grained softened surface to harden.

3. The process claimed in claim 1 including the additional step ofgraining the area defined by the cured last layer and the adjacentsurface of the vinyl base material by:

a. heating the so defined area to soften it;

b. applying a graining tool having the grain pattern of the vinyl basematerial in a die face thereof to the softened area with the die face onsuch softened area;

c. maintaining the graining tool on the softened area under a slightpressure to obtain a grain pattern therein which is feathered with thegrain of the vinyl base material; and

cl. cooling the graining tool while maintaining the slight pressure toallow the grained sofiened area to harden.

4. The process claimed in claim 1 wherein the thermoplastic weldingcompound comprises, in parts by weight, about 0.445 parts of a copolymerof vinyl chloride and polyvinyl acetate, about 0.l50 parts of ahomopolymer of polyvinyl chloride having a fusion temperature of frombetween about 325 to 350 F., about 0.395 parts diisodecyl phalate, andminor amounts of a stabilizer.

5. The process claimed in claim 3 wherein the thermoplastic weldingcompound comprises, in parts by weight, about 0.445 parts of a copolymerof vinyl chloride and polyvinyl acetate, about 0.150 parts of ahomopolymer of polyvinyl chloride having a fusion temperature of frombetween about 325 to 350 F., about 0.395 parts diisodecyl phalate, andminor amounts of a stabilizer.

6. The process claimed in claim 3 wherein the graining tool has abacking with the grain pattern of the vinyl base material, the die facegrain pattern is in register with the grain pattern on the backing, andthe graining tool is applied to the softened area with the grain patternon the backing in index with the grain pattern of the vinyl basematerial.

7. The process claimed in claim 3 wherein the graining tool has abacking with the grain pattern of the vinyl base material.

t i t i

2. The process claimed in claim 1 including the additional step ofgraining the surface of the cured last layer by: a. heating the surfaceof the cured last layer to soften it; b. applying a graining tool havingthe grain pattern of the vinyl base material in a die face thereof tothe softened surface with the die face on such softened surface; c.maintaining the graining tool on the softened surface under a slightpressure to obtain a grain therein; and d. cooling the graining toolwhile maintaining the slight pressure to allow the grained softenedsurface to harden.
 3. The process claimed in claim 1 including theadditional step of graining the area defined by the cured last layer andthe adjacent surface of the vinyl base material by: a. heating the sodefined area to soften it; b. applying a graining tool having the grainpattern of the vinyl base material in a die face thereof to the softenedarea with the die face on such softened area; c. maintaining thegraining tool on the softened area under a slight pressure to obtain agrain pattern therein which is feathered with the grain of The vinylbase material; and d. cooling the graining tool while maintaining theslight pressure to allow the grained softened area to harden.
 4. Theprocess claimed in claim 1 wherein the thermoplastic welding compoundcomprises, in parts by weight, about 0.445 parts of a copolymer of vinylchloride and polyvinyl acetate, about 0.150 parts of a homopolymer ofpolyvinyl chloride having a fusion temperature of from between about325 * to 350* F., about 0.395 parts diisodecyl phalate, and minoramounts of a stabilizer.
 5. The process claimed in claim 3 wherein thethermoplastic welding compound comprises, in parts by weight, about0.445 parts of a copolymer of vinyl chloride and polyvinyl acetate,about 0.150 parts of a homopolymer of polyvinyl chloride having a fusiontemperature of from between about 325* to 350* F., about 0.395 partsdiisodecyl phalate, and minor amounts of a stabilizer.
 6. The processclaimed in claim 3 wherein the graining tool has a backing with thegrain pattern of the vinyl base material, the die face grain pattern isin register with the grain pattern on the backing, and the graining toolis applied to the softened area with the grain pattern on the backing inindex with the grain pattern of the vinyl base material.
 7. The processclaimed in claim 3 wherein the graining tool has a backing with thegrain pattern of the vinyl base material.